GWS F15 bites the big one..but....lives again!

[modfly]

Sadly my F15 is beyond reasonable repair..Pilot Error is the cause of this crash..over confidence and temporally blindness due to flying inverted in to the sun. I had sun glasses on but after cutting some nice aerobatics, rolls loops, inverted flight, I was flying inverted and the plane disappeared to my eyes when I flew in front of the sun..I freaked out and cut the throttle as I could not see the plane..after a short moment I saw the plane, in a steep dive 50' off the deck, I jammed on full throttle and pulled back on the elevator but not enough altitude or speed to pull out...BAM!..This was my worst crash ever :(


I learned something from this..when flying with the sun at 12:00 in your face, you can get blinded and loose orientation fairly easily.

[EDF30]

Killed the same 3s-2100PL batt in a built-up 109 due to melted ESC. The plane's still fine. :D It has one cell that I believe is still fine, but I don't think it will do you a whole lot of good. :eek:
Anyone need a TP 2100PL cell? Seems to still be ok.

That almost happened to my GWS15 at last week's fly-in. Best "in the sun" save I ever had, and mostly sheer luck. The sunglasses went on right afterwards. Had it have gone in, it would likely have hit the announcer's booth. :D

I know this plane well enough and am still amazed that it (not really me, I'll admit) :D managed to regain control. EDFs, and especially this one, do not recover well from diving situations.

Bill

[modfly]

Killed the same 3s-2100PL batt in a built-up 109 due to melted ESC. The plane's still fine. :D It has one cell that I believe is still fine, but I don't think it will do you a whole lot of good. :eek:
Anyone need a TP 2100PL cell? Seems to still be ok.

That almost happened to my GWS15 at last week's fly-in. Best "in the sun" save I ever had, and mostly sheer luck. The sunglasses went on right afterwards. Had it have gone in, it would likely have hit the announcer's booth. :D

I know this plane well enough and am still amazed that it (not really me, I'll admit) :D managed to regain control. EDFs, and especially this one, do not recover well from diving situations.
Bill


Yea..I see..If this had been a prop plane I could have saved it..but being an EDF, once you bleed off air speed.... DOOM!

[corsair nut]

lesson #1..stay away from the dang sun...its nothin' but trouble no matter how you slice it.

[EDF30]

I don't think that I have ever intentionally flown through the sun. :D
You get these people flying 3D in one spot on the flight path of the field at all heights. From now on, I'm done worrying about them. Less chance of hitting them, than crashing from trying to avoid them/watching them instead of your plane.

Last I heard you are supposed to do that stuff in the center of the field, and not right in the flight path, but that's all another story.....

Bill

[CSI]

Oh Modfly, so sorry to see the carnage :o
It's never easy to have one go in like that. I lost my HL Thunderbird EDF to some type of radio glitch..my first jet. I'm sure you have your eye on some new project to make up for it.
I have some expensive fishing type sunglasses I use for my RC flying that do help a lot with the sun glare...saved me a few times!
Good luck with all your other planes and I'm sure you will rebound soon!
Ken

[modfly]

Thanks Ken..yea, its DEPRESSING to loose one like this :( ..one $75.00 lipo shot and the other is banged up but may still be usable. The radio gear appears to have survived. The airframe and lipo is about $175.00 down the tubes..First time I have ever lawn darted one in like that :mad:

[herk1]

Wow sorry to see that. I got my GWS F-15 EPO kit; haven't started building it yet...I want to wait till I have a full build-day available to start.

I've had some really close calls after flying thru the sun. After the last one, I decided to make checking the sun azimuth and height part of preplanning where I'm going to fly the plane. But there are still always those days where I neglect to do one thing or another that I "should" do. Like last week when I flew my Hawk EDF for the second time of the day, and neglected to secure the velcro strap around the battery. First roll-and-push to inverted flight -- out pops the LiPo...it completely disconnected from the Deans. I was a spectator watching the plane flutter down like a leaf into the trees. I was very lucky to have recovered the plane only 12 feet up in a tree, in the middle of a forested area where the trees are over 40 feet, and with not too much damage, but I never found the LiPo ($50 down the drain). As soon as I got home, I painted all my LiPos bright orange (that one was black).

[KiwiKid]

Sorry for your loss. A little trick you may or may not know about is to hold your transmitter in front of your face when you fly into the sun. This shields your eyes from the suns glare, but still gives you control of the model. This is a good trick to remember when you happen to fly into the sun's glare by accident and you only have a few seconds to effect a save.

KiwiKid

[Googleplex]

D'oh! Stupid sun. Shoud be banned. :D

[modfly]

Well..the good news for me is the AR6000 rx and CC-TB-36 survived the crash as I have installed and flown the radio equipment in another plane (T-28). After charging and checking the 2nd TP2100PL lipo, It appears to be functioning normally and is in working order with minor damage..The Pusher Walkera BL motor and new gear box and prop were also undamaged..So I lost the airframe and 1 TP2100..could have been worse. Sunset this evening was at 8:45 EST :rolleyes:

[modfly]

Ok..after getting over the initial shock of the crash I realized this plane could be made to fly again..It won't be pretty, but I think I can repair it..I started gluing it back together today..I will post some pics in a while..

[modfly]

Decided to see if a repair could be done..as It turns out its back together and I'm sure it will be flying again soon..The wings and tailerons, vert stabs are undamaged and thats what matters. The fuse looks a bit ruff but after I use some tape and paint camoflauge..it should look OK from a distance and in the air it will look fine. :D

This plane comes with a spare nose cone..so at least that will look good! :rolleyes:

[gunracer]

repairs are looking sweet...

[stacker]

Little bit of spackle and paint and you will be back in business in no time.

Cheers--Stacker

[herk1]

Spare nose cone?...my kit did not come with a spare nose cone...I just rechecked. It's the EPO one, if that matters.

Looks like you kept the wings removeable (didn't glue them on)...did any of the attachment thingys crack or fail in the crash? Your pictures in the first post show the wings still on...that is encouraging regarding the security of those things.

[modfly]

Spare nose cone?...my kit did not come with a spare nose cone...I just rechecked. It's the EPO one, if that matters.

Looks like you kept the wings removable (didn't glue them on)...did any of the attachment thingys crack or fail in the crash? Your pictures in the first post show the wings still on...that is encouraging regarding the security of those things.

EPO? Hmm..I did not know they had a EPO foam version..yea..mine is the EPS foam and came with a spare nose cone. Yes the wings on mine are still removable and they held even on during the crash..as I said all the flying surfaces were unharmed in the crash and is the reason I decided to repair. I may order a slope kit and do another. This time I would build with elevators and ailerons to save weight in the rear of the plane so that a smaller lipo could be used to balance. I would also redo as a pusher prop like my current one and build a lite weight slow flier version. This plane has the ability to float if it was lite enough.

[modfly]

Well..I don't have video or anything but I did fly the plane last evening and it flew very good. its about 3 oz lighter as I flew with a single Lipo and some dead weight (2.5oz)(I killed the other lipo in the crash) I did notice at this lighter weight that the plane will fly very slow! Its giving me ideas..I may order a sloper and redo a slow flier as this plane has the potential to really float around...I also flew my SM F\A-18 and it is 3 times faster than the F15..The GWS f-15 is just not a fast plane and is more of a "Fighter Glider" IMO. So my next one will be built to exploit that feature..The reason mine is hard to balance is those elevon servos at the rear of the plane weight about 1.25 oz each. I would built the next one with elevator\ailerons instead and I would like to use a 3cell 1300ma lipo to power it..Should make it a floater then.

Edit..during this repair I actually glued the Fuse halves together this time but did it in a way that all the electronics are easily removable. The only thing "trapped" in the plane are the elevon servos and a power harness for the ESC.

[modfly]

Well..I decided to just go ahead and do my "Floater" mod..To windy to fly today so what the hey..I will be adding elevators and ailerons. The object of this mod is decrease the weight in the rear so that a smaller lipo can be used and the overall weight is decreased so the plane will be a lite weight Slow Fighter Glider. Another reason for this mod is to be able to fly in a smaller area.

[herk1]

Congratulations on a successful rebuild! I wonder if EPO would have made a difference in that hard of a crash? Probably not. I got the Park HPX servos for my bird. Would the aileron config. be of any help with the cg compared to just using the Park servos (which are .67 oz. each) for elevon? -- after all, you're adding the aileron servos, pushrods, horns, more glue etc. behind the CG too (albeit not as far behind). For rigging a serviceable fuse, I got some very lightweight plastic attachment hardware. It's kind of like a plastic screw that screws into a plastic tube. My main concern is that I will have to only glue one half of the motor mount stick, which is less secure than gluing it all around. Or I guess I could cut the stick in half like you did. I also will be doing a pusher build. Originally I was planning on using a Scorpion outrunner, but I got a higher-kv Medusa inrunner so that I can use a smaller diameter prop (either 7x5 or 8x4). And this Medusa is pretty powerful. :D

[modfly]

herk1..so the Park servos are less than half the weight of what I was using..Still..I think the A\E setup will require less weight to balance..I'm mounting the elevator servos farther forward than stock. As far as a serviceable airframe..I gave up on this plane as the damage required the halves be joined with glue. However, I figured a way to do it so that nothing is trapped in the plane. I mounted the rx and ESC under the left engine cover and they are easily removable. I also will be changing the engine to a lighter 1100-1500 kv outrunner that will allow the 7.60 prop to be a little higher off the ground.

[gunracer]

very impressive repairs...glad to read she's back in the air...

[modfly]

very impressive repairs...glad to read she's back in the air...

Thanks GR..I have had lots of practice gluing them back together :rolleyes:

Here are some pics of the work completed today..

[modfly]

Decided to just go with elevons and no ailerons..So I'm adding 2 servos. I mounted the servos forward from stock and they are 8g servos. The way I'm setting this up it should be 8oz lighter than before. So I'm looking at an AUW of 32oz. Thats with a single TP2100PL 3cell lipo.

Question..will it fly with the elevators configured as tailerons?

[modfly]

The geared motor I had on here kept getting damaged as it hung down too low. This motor a GWS 005a "Blue" with 2mm shaft was mounted with a 5x35 prop and adapter from a Phase 3 Swoop. I was having trouble finding the rite prop for this motor. It is now a DD drive and there is no way it can get nicked now. This setup draws 11 amps with this prop and seems to have adequate power for this plane.

The "Flying Stabs" on this plane were converted to elevons or tailerons. These are the only control surfaces..no ailerons on this plane. I could easily add them but I want to see what the plane can do with just the tailerons. They do have a lot of deflection and should work fine.


Here is the setup at this point..

GWS F15 airframe(repaired)
Power Harness non removable..all other electronic gear is removable.
2 Imex 8oz servos using Delta mix for tailerons or elevons..
DSM rx
CC TB 36 ESC
1 BB 303 servo for steering nose gear and 2x6'' servo extenders.
3 cell TP2100PL
GWS 005a Blue 4600KV BL motor.
5x35 Prop with 2mm shaft adapter.
1.5 oz nose weight.
AUW 32 oz.

[modfly]

I'm off to go fly it. Flight report when I return..


10:00 pm EST
edit..just got back and it flew good :) Seemed under powered and I realized I had limited the 2nd throttle endpoint to 58%. I also moved the balance point aft a bit..Flys like it still has flying stabs..The flying speed was real slow due to the throttle limit. The Lipo gets very hot in this plane..not enough airflow..actually there is no airflow to the lipo and this is a major flaw in this design as heat kills lipos so I'm going to have to do something..I'm thinking of mounting it on the bottom of the plane so its exposed to airflow or maybe a air scoop IDK..Everytime I use this motor, seems the lipo gets real warm..I don't get it as I was only drawing around 110 watts from the lipo. I have a lite weight Outrunner I'm trying next..I guess I'm using this airframe to find the optimum power and control setup for the F15 to suite my tastes.

[EDF30]

Moved to Pushers

There's a prop on the back of it now. :D

Bill

[modfly]

No..its not moved to pushers. I still have the twin edf units and will reinstall after a while and this is about control surface mods and not the propulsion unit. I have ordered some new lipos from hobby city as the ones I was using were damaged and or destroyed and this proportion unit is temporary until I get the new long max lipos so this thread will stay here Bill.

[skyhawk]

If your batteries are getting hot, I guess with no draw from the fan through the exits in the duct - not much air goes though the cooling hole at the front.

[herk1]

Wow did you really use the GWS 4600 kv inrunner motor direct-drive, with a prop? :eek:

[modfly]

Wow did you really use the GWS 4600 kv inrunner motor direct-drive, with a prop? :eek:

Yes I did ;) I limited it to 11 amps and it seemed to work good. I don't have a good tach but it sounded like it was spinning that prop pretty fast...sounded like a Jet. When I get time I'm going to put it on a thrust stand and see what its doing thrust wise.


I flew the GWS F15 6 times through out the day. Its flying with elevators only and is doing very well. Every time I put it in the air, people notice and stop what they are doing and watch it fly around. I made several new acquaintances today flying this plane at the mall lot.

The mall is closed on sunday so I have whole the lot to my self :)

[herk1]

Going with elevators instead of full-flying stabs, then using them as elevons, sounds like the system on those little Kyosho hand-launch thingys. What kind of roll rate are you getting? And flying a 2-lb. plane on 11 amps...so you've got about 60 watts per pound?...while using that motor DD with a prop...interesting, just goes to show you never can tell what might work till you try.

[modfly]

herk1..the roll rate sucks but it will roll although it loses altitude doing it. Yea the plane got trashed and I thought well, experiment time..Today.....I also ran it off a PZ 1800 mah from a T-28 and that worked fine. I'm getting an easy 10 minute flight from each of my lipos so the thing was in the air 1 hour today between the 6 flights. I'm amazed at how well the elevators work as the only control surface. Yep..60 watts per pound..thats amazing to me. Thats plenty of power by the way for a nice scale ROG....this thing is just a big glider and it looks so cool in the air. Believe me..I don't have to do any aerobatics to draw an audience..All I do is some yank and bank maneuvers and fly low to the ground then pitch up for slow mo landings..People have applauded when I do that..I have even been thanked for the air show. This plane just looks so awesome in the air I fly it up real high so people on the main road can see it and that brings them in to the mall lot to watch the flight. I'm posting this info for people that may be interested in keeping the plane aloft cheaply as apposed to speed mods and such. Shoot..with this new found knowledge about the elevators, I could throw a 3 channel rx in this thing and fly it as a cheap and dirty grass landing belly flopper. When I first put this plane together It was a ~400 watt monster that cost a small fortune to outfit..so after the crash and subsequent repair, I wanted to know what the minimum configuration was I that is what I have now. I'm actually having more fun with it in the minimum configuration and I'm getting much more flight time.